An English physician who spent his early years studying fossils and birds, Edward Jenner discovered a vaccination for smallpox disease in 1796. His experiments paved the way for the modern science of immunology. Researchers continue to follow in Jenner’s footsteps, working to develop cures for problems such as arthritis and AIDS.

Born in Berkeley, Gloucestershire, England, on May 17, 1749, Edward Jenner grew up intensely fascinated by biology. He spent his early years collecting fossils and studying the nesting habits of cuckoos.

According to the Jenner Museum, at the age of 14, he began a seven-year apprenticeship under Dr. Daniel Ludlow to become a surgeon. Jenner moved to London to finish his medical training under John Hunter, who became a lifelong friend, and in 1772, he returned to Berkeley to work as a surgeon and general practitioner.

Meanwhile, smallpox, which Mayo Clinic explains is a contagious and often deadly disease, ran rampant throughout Europe. Victims initially experienced flu-like symptoms, such as fever and vomiting, before breaking out in a rash of pus-filled blisters that left behind deep scars. Jenner turned his attention to studying this disease during the last two decades of the 18th century.

The Modern History Sourcebook describes that while living in the English countryside, Jenner kept detailed observations of cases of smallpox and cowpox, a similar but not fatal disease. He noticed that milkmaids, frequently exposed to cowpox from milking animals, were immune to smallpox.

In his famous 1796 experiment, Jenner infected 8-year-old James Phipps with cowpox. Six weeks later, according to the BBC, when Jenner exposed Phipps to smallpox, the boy was immune, proving that inoculation with cowpox could provide resistance against the fatal disease.

The Royal Society deemed Jenner’s experiment “too revolutionary” and lacking in proof, but by repeating the experiment on more children, including his own son, Jenner was able to publish his findings in 1798. In his paper, he coined the term vaccine after the Latin word for cow (“vacca”).

Jenner, suddenly famous for his discovery, spent the next several years fielding questions about the treatment and calling himself “the Vaccine Clerk to the World,” according to the Jenner Museum. After his wife, Catherine, died in 1815, Jenner resorted to his earlier hobbies of collecting fossils and gardening.

On the morning of Jan. 25, 1823, he was found lying unconscious in his library. Jenner had suffered a stroke and died the following morning at the age of 73. He was buried alongside his family in Berkeley Church. His home has since been transformed into the Edward Jenner Museum, a tribute to the physician’s life and work.

Although Jenner’s research initiated the spread of smallpox treatment across Europe and North America, it did not completely wipe out the disease for another 180 years. However, MSN Encarta explains that Jenner's work inspired other scientists and doctors to search for cures, beginning with French chemist Louis Pasteur in the late 19th century.

According to PBS, The World Health Organization finally declared smallpox eradicated in 1980.